176896

Appears in sequences

• Triangle of coefficients in expansion of D^n (tan x) in powers of tan x.at n=30A008293
• Triangle of tangent numbers.at n=25A008308
• Expansion of e.g.f.: cosh(log(1+sin(x))).at n=10A009123
• E.g.f. (1/2) * tan(x)^2 (even powers only).at n=5A024283
• Triangle T(n,k) (1 <= k <= n) of tangent numbers, read by rows: T(n,k) = coefficient of x^n/n! in expansion of (tan x)^k/k!.at n=46A059419
• Triangle T(n,k) (n >= 1, 0 <= k <= floor((n-1)/2)) read by rows, where T(n,k) = (k+1)T(n-1,k) + (2n-4k)T(n-1,k-1).at n=29A101280
• Triangle read by rows: nonzero coefficients of the polynomials F_n(x) which express derivatives of tan(z) in terms of powers of tan(z).at n=33A101343
• Triangle T(n,k), 0 <= k <= n, read by rows, defined by T(0,0) = 1; T(0,k) = 0 if k < 0 or if k > 0; T(n,k) = k*T(n-1,k-1) + (k+2)*T(n-1,k+1).at n=46A107729
• Triangle of tanh numbers.at n=57A111593
• Denominator of 2*n*A000111(n-1)/A000111(n): approximations of Pi using Euler (up/down) numbers.at n=10A132050
• Sum of the principal diagonals of a 2n X 2n square spiral.at n=32A137931
• Triangle of coefficients of the polynomials (1 - x)^n*A(n,x/(1 - x)), where A(n,x) are the Eulerian polynomials of A008292.at n=59A141720
• Triangle read by rows: coefficients in polynomials P_n(u) arising from the expansion of D^(n-1) (tan x) in increasing powers of tan x for n>=1 and 1 for n=0.at n=57A155100
• E.g.f.: sec(x)^3+(sec(x)^2*tan(x)).at n=9A225688
• E.g.f.: sec(x)^2*tan(x)+sec(x)*tan(x)^2.at n=9A225689
• a(n) is the numerator of polygamma(2n+1, 1) / Pi^(2n+2).at n=5A255006
• Related to Euler numbers, expansion of e.g.f. tan(x)^2.at n=8A259688
• E.g.f.: C(x,k) = 1 + Integral S(x,k)*D(x,k)^2 dx, such that C(x,k)^2 - S(x,k)^2 = 1, and D(x,k)^2 - k^2*S(x,k)^2 = 1, as a triangle of coefficients read by rows.at n=19A322231
• E.g.f. S(x,y) = sin(x) / sqrt(1 - sin(x)^2 - sin(y)^2).at n=16A324610
• E.g.f. S(y,x) = sin(y) / sqrt(1 - sin(x)^2 - sin(y)^2).at n=19A324612